And thus china used this to play santa, and nullify the chinese border for ever, as India now has to manage constant engagement.
See, Pakistan makes India's job easy. You treat Afghanistan as your backyard, that creates automatic resentment in thier leadership. Even now your establishment's rhetoric is without Islamabad's backing there will be no peace, like you control the tap through which peace flows.
My estimate is US will stay longer, keep Pakistani involvement in check, assymetric stuff will continue, in next two decades parts of afghanistan will develop and be a non hostile government to India. India will keep it's infrastructure development in afghanistan and forge better relations.